Closure for tube holes



Dec. 6, 1955 R. E. MOORE CLOSURE FOR TUBE HOLES Filed Aug. 11, 1953 v gIAgEA/TOR.

--2,725,72- 7 CLOSURE semen noLns Robert E. Moore, Amana, Iowa, assignor to Amana Re frigeration, Inc Amalia, Iowa, a-=corpora'tion of lowa Application August ll, 1953, Serial No. 373,379 3 Claims. -'(Cl. 62- 89) This invention relates to freezer cabinets and the like, and has particular application to a domestic food freezer provided with shelves having refrigerant "coils mounted directly thereon.

It is a primary object o f'the invention -'to provide 'ashelf and cabinet liner construction whereby the evaporator coils utilized for cooling individualshelve's in anupright freezer may be installed therein in an easy, convenient and economical manner, yet wherein the parts of the freezer liner, shelf and evaporator co ilsare so'relatedthat the interior of the cabinet is neat, attractive 'an'd 'h'as a properly finished appearance. I

A further object of the invention is -the provision of a freezer liner and shelf assembly so jiiesigned and 'c o'nstructed as to render it "entirely practicable to "provide relatively large oversize clearance holesin the back or side walls of the freezer liner, s'othatadequateclearance may be afforded to refrigerant tubes passing therethrough, yet

" tes area to provide a simple, economicahand practicable means for concealing these holes in the liner so'that the appearance of the interior of the freezer isnot marred'by such apertures.

A still further object of the invention is thesprovision of a metallic freezer liner and shelf construction wherein clearance holes for refrigerant tubing passing through the walls of the liner may be made sufficiently large as to provide adequate manufacturing tolerances for the positioning and mounting of shelves within the cabinet, yet wherein the holes in the liner may be completely sealed in a manner to prevent the passage of moisture therethrough.

Afurther related object is the provision of a freezer liner and shelf assembly wherein relatively large apertures required to accommodate refrigerant tubes passing through the vertical walls of the liner are adequately concealed by the flanges normally used to secure the freezer shelves to said liner walls.

In the present state of the domestic freezer art, it is more or less common practice to provide upright freezer cabinets with an exterior metal shell and an interior sheet metal liner, spaced apart from each other and separated by a layer of thermal insulating material to avoid heat transfer between the liner and the exterior shell. It is also common practice to fabricate a number of horizontal shelves Within the cabinet liner. in many instances, these shelves are fabricated of sheet metal such as aluminum, and they may each be provided with an evaporator coil of a refrigerating system, so that each shelf is an active refrigerating surface. Obviously, this expedient makes for freezing efficiency, since foods placed within the freezer are in direct contact with the freezing surfaces of the shelves.

There has been difiiculty in the past, however,'in fabricating and assembling the freezer shelves and their evaporator coils in such a manner as to permit adequate manufacturing tolerances and yet maintain a neat and finished appearance within the interior of the cabinet. This arises primarily by reason of the fact that it is desirable to provide the freezer liner with clearance holes very considerably larger than the diameter of the refrigerant tubing passing through them, in order that the shelves may easily be inserted into their positions within the interior of the cabinet, and so that they do not require unduly precise positioning therein.

The present applicant proposes a construction wherein adequate clearance and ample tolerances are available, yet wherein the oversize clearance holes in the liner wall are completely and permanently concealed in the finished cabinet. The preferred mannerof accomplishing this result is best described in connection with the-drawings of this specification attached hereto, wherein:

Figure 1 is a perspective view of one of the shelves of a freezer constructed in accordance with the present invention, the shelf being inverted to show the evaporator coils secured on the under side thereof;

Figure 2 is 'a rear elevational view of a typical freezer liner assembly, showing the manner in which the end 'tubesofthe evaporator coils of Figure 1 extend through the back wall of the liner and between the several shelves of the assembly for interconnection to each other;

Figure 3 isa detail sectional view taken on the plane of the line 33 of Figure l; and

Figure 4 is a fragmental detail sectional view taken substantially on the plane of the line 44 ofFigure 2, and showing the details of the construction of the upright back wall of the freezer liner and the shelf flange affixed thereto.

The freezer shelf l0, illustrated inFigure 1 of thedrawings, includes aflat top plate 1-1, --with a front flange 12, back flange 13 and side "flanges 14 and IS. The entire shelf is preferably formed ofa single pieceof sheet metal of high thermal conductivity, such as sheet aluminum. A plurality of these horizontal freezer shelves 10 may be mounted in a freezer liner having upright side walls 21 and22,fand back wall 23. These -wallsmay:a'lso befabricated-o'f 'a single sheet of aluminum, if desired. The entire liner and shelf assembly of Figure '2 is housed within an exterior metal sheet and provided with appropriate thermal insulating material, but inasmuch as these parts may be conventional, they are not illustrated in the present drawings.

Each of the freezer shelves is preferably provided with a coil of refrigerant tubing 16 securedto its under side. In practice, the coil may be secured to the under side of the metal by brackets or clips spot welded to the sheet metal of the shelf, or it may be brazed thereto as indicated at 17 (Figure 3). In either case, the portion of the coil attached to the shelf is provided with outwardly extending end tubes consisting of an inlet connection and outlet connections 18 and 19 whereby the evaporator coils of each individual shelf may be joined in series with the coils of the next adjacent shelf above and below it (see Figure 2).

In the process of constructing the cabinet it is deemed desirable to first secure the evaporator coils to their individual shelves, and to thereafter assemble the several shelves within the liner. In constructions wherein the refrigerant coils are brazed to the shelves, it is the practice to clamp the refrigerator tubing to the sheet metal of the shelf with strips of aluminum brazing material secured at proper intervals, and to then pass the entire shelf assembly through a furnace with a reducing atmosphere, so that the coiled tubing is firmly and permanently secured to the shelves prior to assembly of the individual shelves in the freezer liner. The individual shelves are then inserted into the positions illustrated in Figure 2 and secured therein by any convenient means, as by spot welding the flanges 13, I4 and 15 to the back wall 20 and side walls 21 and 22 of the freezer liner.

In order to assemble the shelves within the liner with easeand facility, it is essential that the holes provided in the back wall of the liner be considerably oversize. That is, they must be sufliciently larger than the refrigerant tube so that the ends of the tube may be conveniently inserted through the holes and so that the shelves may be located in their correct positions without interference arising from contact between the refrigerant tubes and the holes in the liner. Thus when the shelf is being assembled within the liner and the tube is inserted through the oversize hole, there is an extremely loose fit and a considerable amount of play between the refrigerant tube and the oversize hole. It is nonetheless essential that all holes through the liner be completely sealed to avoid migration of moisture through the metal liner Wall. It is also highly desirable that all holes be completely concealed from view from the interior of the liner, so that they do not detract from the appearance of the interior of the freezer cabinet.

These objects are accomplished in the present invention by providing the back flange 13 of each of the shelves 10 with a pair of apertures 23 and 24 dimensioned to fit closely around the end tubes 18 and 19 of the refrigerant coils 16. Preferably, these tube ends are sealed in the openings 23 and 24 by aluminum brazing material which forms fillets 25 (Figures 3 and 4) when the refrigerant tubing is brazed to the bottom of the individual shelves.

The individual shelves are assembled within the metallic liner by inserting them from the open front thereof. I The end tubes 13 and 19 of the refrigerant coils 16 pass through oversize clearance holes 26 provided in the back 'wall 20 of the liner, but these oversize holes are completely covered and concealed by the shelf flanges 13 (Figure 4). The end tubes 18 and 19 of each refrigerant coil are preferably joined to a corresponding tube coming from the next shelf by a brazed joint 27.

If desired, the large clearance holes in the back wall of the liner may be filled with mastic or other sealing compound 30, to assure a completely airtight seal between the interior of the liner and the insulation space surrounding it.

From the foregoing it will be apparent that the teachings of the present disclosure provide a simple, convenient and inexpensive method of fabricating and assembling the liner and shelves of an upright freezer, yet provide a completed structure wherein the clearance holes in the liner wall are completely closed andconcealed. As a consequence, the wall of the liner is rendered entirely airtight and any possibility of vapor migration through the wall is eliminated. The interior appearance of the cabinet is neat and attractive, yet the assembly of liner and shelves is accomplished without necessity of maintaining close manufacturing tolerances.

Having thus described my invention, what I claim as new and desire to secure by United States'Letters Patent 1.. In a freezer including a freezer liner having an up right wall, at least one divider mounted upon said wall and extending generally perpendicular thereto, an evaporator coil positioned against one surface of said divider and having at least one end tube thereof projecting beyond the edge of said divider and extending through said upright wall, an oversize clearance hole in said upright wall surrounding said end tube whereby an extremely loose fit is provided, and mastic means for sealing the junction between said end tube and said upright wall, said divider having a flange extending generally parallel to said upright wall, and adjacent thereto and having an aperture therein fitting loosely around said end tube.

2. The invention as described in claim 1, said flange having a width greater than the diameter of said oversize clearance hole in said upright wall and extending entirely over'said hole wherebythe oversize clearance hole is concealed from view.

3. The invention as described in claim 2, said evaporator coil beingin heat exchange relationship with said divider and brazing means therebetween whereby the thermal conductivity is increased.

References Cited in the file 'of this patent UNITED STATES PATENTS 2,070,457 Steenstrup Feb. 9, 1937 2,405,834 Kleist Aug. 13, 1946 2,446,895 Weiss Aug. 10, 1948 2,489,754 Crider Nov. 29, 1949 2,490,995 Chapman Dec. 13, 1949 

